Alien Intelligence

[tomBitonti]

Re: What is the chance we are the first intelligent life in the universe.

That would seem to depend on parameters which we don't know.

If we assume that life could arise anytime after, say, population II stars began forming, with a minimum time life to arise around a star, and that the chances don't change very much for some long period of the universe (starting after a fixed time, and ending at a later time, and roughly constant during that time), and if the process were memory-less, then an exponential distribution could be used as candidate distribution.

For an exponential distribution, the rate parameter would make a huge difference as to whether we are first: With a low parameter (say, 1 every billion years, starting at say, 5 billion years), we would very probably not be first.

With a rate parameter more like 1 every 10 billion years, starting after 5 billion years, then the probability might be that we are first.

For a much longer rate parameter, say, 1 every 50 billion years, then we would almost definitely be first, (and very lucky).

If the rate parameter has a value very much smaller than 1 every billion years, we might have to change the question to whether we are first in our galaxy. If the rate is 1 every 10 billion years per milky way sized galaxy, then we should be one of billions of life forms, and very very probably not the first.

The problem sounds like a nice probability problem: Assuming an exponential distribution that determines the probability of intelligent life arising starting at 5 billion years, and with a given rate parameter (set in units of 1/billion years), what is the chance that life which arises after a given number of years is first?

It might be interesting to do a bayesian analysis to see if the timing of our arrival can tell us anything about the probable rate parameter. Or maybe not, since we have only one data point, and the shift in the post and posterior distributions might not change the expectation of us being first.

Thx!

TomB

 

[Ryujin]

No, actually. Pessimism, by definition, over-weights probabilities to one side, and therefore is not realistic. But, pessimists frequently make claim to being realistic.

But - real science now: We only have one planet with life on it that we know about*. That means no statistically relevant sample set, and thus no real understanding of the probabilities. Statements as to what are "realistic expectations" are therefore hubris. The only way to gain more information to decide the question either way, is to *look* for it. And looking for it honestly requires a mind open to the possibility. Deciding you already know the answer is the antithesis of scientific inquiry.



*And, despite the claim that we have been looking for decades - our technology is, at best, only recently really up to the challenge, and the funding has never been there for anything like a comprehensive approach.

And excessive optimism is no more realistic than is being overly pessimistic, but I would argue that saying there is no one else out there, because the odds are just too long, is the pessimism that we're talking about here. My mind is open to the possibility. In fact I consider it to be a high order of likelihood that other intelligent life exists out there, though that could also be seen as "hubris." I simply lean to the side that life is rare and special, rather than ubiquitous.

Keep in mind, as I've been saying, that it's a matter of them looking for us as much as us looking for them.

 

[Jhaelen]

The trick is to figure out how those alien life forms THINK in different ways from us. What are alien ethics? Cultures? Gets tricksy...

I like Stanislaw Lem's take on this. The recurring theme of his novels is that aliens are so utterly 'different' from us that there's practically no chance to ever communicate with them in a meaningful way. Take your pick (or better read them all!):
- Solaris,
- Fiasco,
- Eden,
- His Master's Voice,
- The Invincible

 

[Janx]

It's interesting how most scifi shows are very limited in their scope. Most are this galaxy, or a single galaxy. Fewer span multiple galaxies.

You should know 400 billion from playing Eliteangerous. That's about how many stars there are in the Milky Way (and thus how many stars they put in the game)

Given the size of our galaxy, I usually find it a case of make-it-bigger-ism to go beyond the current galaxy. The gap between them is so huge that it's improbable to reach if you haven't fully explored and conquered the current galaxy (which is also nigh-impossible to complete).

 

[Morrus]

You should know 400 billion from playing Eliteangerous. That's about how many stars there are in the Milky Way (and thus how many stars they put in the game) .

I knew 400 billion many, many years before Elite: Dangerous ever existed.

 

[Hand of Evil]

One of the problems I see is not is there intelligent life out there, is there intelligent life out there at the same time? The window is very small.

 

[Janx]

One of the problems I see is not is there intelligent life out there, is there intelligent life out there at the same time? The window is very small.

that and everybody is just so darn far away. we and they aren't likely to come visiting any time soon. If they make a radio, the signal takes forever to get here. AND we have to be listening at the right time.

what if aliens existed on the opposite side of the galaxy and they setup a transmitter 200,000 years ago that ran for 90,000 years. that means the transmissions passed us and stopped 10,000 years ago, long before we invented a radio to hear them.

We may not be alone in the galaxy, but for practical purposes, we are alone.

 

[Morrus]

Or at least unless we discover that FTL communications are possible.

 

[tomBitonti]

If intelligent life persists, then it should eventually be able to make Van Neumann probes and have them be nearly everywhere in the galaxy. We might be only a century or so away from doing this ourselves.

Then, if intelligent life exists and is serious about contacting other life forms, it should be able to do so. Whether the message was fixed would depend on whether the probes setup a message forwarding network. The message would either be fixed, or would have a latest update on some forwarding interval.

I think you get back to the Fermi Paradox pretty quickly. Perhaps limited to intelligent life similar to us in technology and that persists.

Aside, not sure if this has been covered: Here is a different equation kindof in the same area as the Drake quation:

http://io9.com/what-a-brand-new-equation-reveals-about-our-odds-of-fin-531575395

This wonderful story from Brin -- "Lungfish", C 1987 from "The River of Time" short story collection -- is a nice take on the problem:

http://www.astro.sunysb.edu/fwalter/AST389/TEXTS/lungfish1.txt

Thx!

TomB

 

[Umbran]

If intelligent life persists, then it should eventually be able to make Van Neumann probes and have them be nearly everywhere in the galaxy. We might be only a century or so away from doing this ourselves.

Not necessarily. There is a major question as to whether technology will ever allow anyone (human or otherwise) to build devices that can last for the required centuries of exposure to interstellar space without maintenance.